This grant, made through the Major Research Instrumentation (MRI) Program, provides partial support of the costs of acquiring a stable isotope facility to study Earth and environmental processes at the University of Nevada, Reno. The facility will be composed of two major components, which have been selected based on the large numbers of analyses anticipated for the facility, and the diverse nature of the studies to be supported by this instrumentation, requiring analysis of a broad range of sample types (liquids, solids, gases, dissolved components). First, a dual inlet stable isotope ratio mass spectrometer with H/D collectors and a multi-sample manifold, which will be used for the analysis of various samples prepared off-line (e.g. silicates, carbonates, waters). Second, a single inlet - continuous flow stable isotope mass spectrometer equipped with H/D collectors, a gas chromatography - combustion/pyrolysis unit, and an elemental analyzer. This will be used for studies requiring high sample throughput (e.g. ecological studies), and for studies requiring C and H isotope analysis of individual organic compounds within a complex mixture. Specific examples of ongoing and planned research activities that will benefit from this instrumentation include the study of: the origin of Carlin-type sedimentary hosted gold deposits; the geochemistry and geothermometry of active and fossil geothermal systems; the geochemical behavior of sulfur in ore-related igneous rocks; the stable isotope geochemistry of organic contaminants in ground water; the biogeochemical behavior of nitrogen in forested ecosystems as recorded in tree rings; the magnetite - water fractionation factor at low temperature; early diagenesis and paleoceanography in the Black Sea; biogeochemical cycling of nutrients at Lake Tahoe; dolomitization events in the Great Basin; and continental paleoclimate in western North America. ***
